JPH11304599A - Temperature sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable highly accurate temperature measurement by securing a temperature detecting part in which a temperature sensing element is formed on a substrate to the end face of a heat transferring member, connecting it to an output terminal, and molding the half parts of the temperature detecting part, the heat transferring member, and the output terminal. SOLUTION: An insulating layer, a thin-film temperature sensing element, and an insulating layer are sequentially laminated on a substrate to form a chip-shaped temperature detecting part 2. The upper end face of a heat transferring member 3 is secured to the temperature detection part 2 via a cement so as to be opposed to the surface of the temperature detecting part 2 on the side of the thin-film temperature sensing element 8. The temperature detecting part 2 is connected to an output terminal 4 by a bonding wire 13, and the upper half parts of the temperature detecting part 2 and the heat transferring member 3 and the lower half part of the output terminal 4 are coated with a coating member 5. Therefore, water does not seep into the temperature detecting part 2 to destroy its detecting circuit, or dust and solid particles do not adhere to the surface to degrade temperature characteristics. By this, it becomes possible to measure temperature with high accuracy at a local section.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature sensor which is attached to an appropriate place such as a cooling / heating apparatus, a hot water supply apparatus, and is used for measuring the temperature of the place.

[0002]

2. Description of the Related Art Conventionally, a cooling / heating air outlet of a cooling / heating device,
A temperature sensor with a built-in thermistor is used to measure the temperature of air near an indoor air inlet, the temperature of hot water stored in a water storage tank of a water heater, and the like. As such a temperature sensor, for example, a temperature sensor 101 as shown in FIG. 8 and a temperature sensor 201 as shown in FIG. 9 are known.

The temperature sensor 101 is connected to one end of a thick-film thermistor 102 by hooking a core wire 103a of a lead-out cord 103 and soldering the hooked portion 104. Then, a silicone resin 105 is adhered to the vicinity of the thermistor 102, covered with a polyolefin resin tube 106, and further, the silicone resin 105 is adhered to the tube 106 and the leading end of the lead-out cord 103,
It is covered with a tube 107 made of polyolefin resin. The temperature sensor 201 is a thick film thermistor 20.
2 is connected to one end of the lead cord 203 by soldering 204 a core wire 203a. Then, after covering the thermistor 202 with a vinyl chloride resin tube 205, the thermistor 202 and the leading end of the lead cord 203 are inserted into a stainless steel circular tube 206 having a closed distal end. Silicone resin 20
7, and a sealing member 208 is fitted and sealed in the latter half.

[0004]

SUMMARY OF THE INVENTION The above temperature sensor 10
Each of the core wires 103a and 203a is obtained by soldering the core wires 103a and 203a to the thermistors 102 and 202.
The core wires 103a and 203a have a relatively large diameter with a high tensile strength so that the solder wires 3a and 203a are cut and the solder does not peel off.
It had to be about 0.3 to 0.5 mm. In order to measure the temperature with high accuracy, the core wires 103a, 203
a has a relatively large diameter, so that the core wires 103a, 203a
The influence of the heat flowing into or out of the thermistors 102 and 202 through the heater cannot be ignored.

For this reason, in the temperature sensor 101, the silicone resin 105 is attached to the tube 106 and the leading end of the lead-out cord 103, and the polyolefin resin tube 10 is formed.
7, in the temperature sensor 201, the thermistor 202 and the leading end of the lead-out cord 203 are inserted into the stainless steel pipe 206, and the stainless steel pipe 2 is inserted.
06 is filled with the silicon resin 207 to form a portion having a uniform temperature for a long time.
This reduces the inflow or outflow of heat through 3a, thereby reducing the effect on measurement accuracy.

Thus, the conventional temperature sensor 101,
In 201, since a long uniform temperature portion is formed, an average temperature is actually measured in a wide range to some extent, and high-precision temperature measurement in a local portion cannot be performed. .

The conventional temperature sensors 101 and 201 both have the core wires 103a and 203a soldered, and the silicone resins 105 and 207 are attached or filled therein.
It is necessary to perform a troublesome work that is difficult to automate, such as covering 06, 107 and 205, and the manufacturing cost has to be increased.

[0008] A thick-film or thin-film thermistor can measure the temperature with high accuracy and high-speed response because the volume of the temperature-sensitive body is small. May be mounted by soldering. However, simply by soldering to a printed circuit board, if the device is placed in high-humidity air or if the surface of the thermistor is condensed, moisture may enter the thermistor and damage the detection circuit, When dust, solid particles, etc. adhere to the surface of the mr, there is a problem that the temperature characteristics of the thermosensitive body deteriorate.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to enable high-precision temperature measurement at a local portion, thereby reducing manufacturing costs. It is another object of the present invention to provide a temperature sensor which has good environmental resistance characteristics and which does not easily break a detection circuit or deteriorate temperature characteristics.

[0010]

In order to achieve the above object, a temperature sensor according to the present invention is characterized in that a temperature detecting portion having a temperature sensitive body formed on a substrate is fixed to an end face of a heat transfer member, and the temperature detecting portion is provided. The unit and the output terminal are connected by a bonding wire, and the temperature detecting unit, the heat transfer member, and a half of the output terminal are covered with a covering member molded.

Here, the heat transfer member may be a rectangular thin plate, or a thin disk portion fixed to the tip of the rectangular thin plate portion.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the temperature sensor according to the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the temperature sensor 1 comprises a temperature detecting section 2, a heat transfer member 3, an output terminal 4, and a covering member 5.

As shown in FIG. 2, the temperature detecting section 2 is a chip formed by sequentially laminating an insulating layer 7, a thin film temperature sensing element 8, and an insulating layer 9 on a substrate 6.

The substrate 6 is a rectangular plate made of silicon, alumina, or the like and having a thickness of about 600 μm and a size of about 2 × 3 mm. As shown in FIG. 550 μm deep from the surface by etching etc.
Recess 10 is formed. Then, on the opposite surface where the insulating layers 7 and 9 and the temperature sensing element 8 are laminated, a film thickness 50 made of glass is formed.
A preparation 11 having a thickness of about 200 μm is fixed, the recess 10 is completely sealed, and an air layer is provided here.

The temperature sensing element 8 has a thickness of about 0.5 to 1 μm and is a metal resistive film having a large temperature coefficient such as platinum or nickel patterned in a desired shape, for example, a meandering pattern, or a manganese oxide-based or silicon carbide-based film. NTC thermistor, PCT
It consists of a thermistor. The insulating layers 7 and 9 have a thickness of 1 μm.
Of SiO ₂ .

The heat transfer member 3 is made of a material having good thermal conductivity such as copper, duralumin, and a copper-tungsten alloy, and is a thin rectangular plate having a thickness of about 200 μm and a width of about 2 mm.

As shown in FIG. 1, the temperature detecting section 2 is provided with a bonding material such as a silver paste or the like in which the surface on which the insulating layers 7, 9 and the temperature sensing element 8 are laminated is opposed to the upper end surface of the heat transfer member 3. 12 is fixed. Then, the temperature detecting unit 2 and the output terminal 4 are connected by a bonding wire 13, and the covering member 5 obtained by molding the temperature detecting unit 2, the upper half of the heat transfer member 3 and the lower half of the output terminal 4. Coated. Here, the diameter of the bonding wire 13 is 10 to 5
The distance between the output terminal 4 and the heat transfer member 3 is preferably 0.2 mm or more, particularly preferably 1 mm or more.

As described above, the temperature sensor 1 of the present invention
Bonding wire 1 between temperature detecting section 2 and output terminal 4
3, the amount of heat flowing into or out of the temperature detecting unit 2 via the bonding wire 13 is very small. Therefore, unlike the conventional temperature sensor, it is not necessary to form a long uniform temperature portion. Therefore, the vicinity of a portion where the heat transfer member 3 which is a rectangular thin plate protrudes from the covering member 5, that is,
It is possible to measure the temperature of air, hot water or the like at a local location with high accuracy.

In the temperature sensor 1 of the present invention, since the temperature detecting section 2, the upper half of the heat transfer member 3 and the lower half of the output terminal 4 are covered with the covering member 5, The detection circuit is destroyed due to the intrusion of moisture into the
There is no possibility that dust, solid particles, etc. adhere to the surface and the temperature characteristics are degraded.

Further, as in the present embodiment, a concave portion 10 is formed in the substrate 6, an air layer having a high heat insulating effect is provided, and insulating layers 7, 9 and a temperature sensing element 8 are provided on the upper end surface of the heat transfer member 3. The temperature sensing unit 2 is fixedly attached with the surfaces on which the layers are stacked facing each other, and the area where the temperature sensing element 8 contacts the covering member 5 is reduced as much as possible.
Since the amount of heat held by the temperature sensing element 8 and the amount of heat transmitted through the heat transfer member 3 rarely flow into or out of the covering member 5, more accurate temperature measurement can be performed.

Although various methods can be employed for manufacturing the temperature sensor 1, the heat transfer member 3 and the output terminal 4 may be integrated. For example, as shown in FIG. 4, after the plate material 14 is etched to form a plate base material 15 having a predetermined shape, a portion where the temperature detection unit 2 is joined is sequentially subjected to silver plating, and a silver paste is applied. The temperature detector 2 is fixed, and the temperature detector 2 and the output terminal 4
Are connected by wire bonding, and the heat transfer member 3
The portion corresponding to is plated with nickel. Then, the temperature detector 2, the upper half of the heat transfer member 3, and the lower half of the output terminal 4 may be molded with epoxy resin to manufacture the temperature sensor 1 as shown in FIG.

As described above, in the temperature sensor 1 of the present invention, the plate material 14 is etched, silver-plated, the temperature detecting section 2 is fixed, connected by wire bonding, nickel-plated, and molded with epoxy resin. In this case, since all the steps can be automated, the manufacturing cost can be significantly reduced.

Next, a method of using the temperature sensor 1 according to the present invention will be described for a case where the temperature of Freon gas flowing through a conduit is measured.

For example, a measuring casing 16 as shown in FIG. 6 is used. The measuring casing 16 includes a main body 17 made of a synthetic resin such as a vinyl chloride resin and a lid 18 detachable from the main body. The main body 17 has a metal conduit 19 made of copper or the like penetrated therethrough. The conduit 19 has flange portions 20 and 20 formed at both ends and a raised portion 21 at an intermediate portion, and a screw hole 21a is formed in the raised portion 21 by screwing. On the other hand, the heat transfer member 3 of the temperature sensor 1
a is drilled in advance.

First, the flanges 2 of the conduits 22, 22 through which the fluorocarbon gas flows, flow through the flanges 20, 20 of the conduit 19.
3 and 23, and bolts are tightened so that conduits 22 and 22
The measurement casing 16 is arranged and fixed in between. next,
The heat transfer member 3 of the temperature sensor 1 is placed on the raised portion 21 of the conduit 19, and a screw 24 is inserted through the insertion hole 3 a, and the screw hole 21 a
Screw. As a result, the amount of heat possessed by the Freon gas flowing from the conduit 22 and flowing through the conduit 19 is transmitted to the heat transfer member 3 via the screw 24 and the raised portion 21, and the temperature detector 2 detects this amount of heat. Therefore, the temperature of the CFC can be measured.

In the above embodiment, the heat transfer member is a rectangular thin plate. However, as shown in FIG. 7, the heat transfer member 25 may be formed by fixing a thin circular plate portion 25b to the tip of a rectangular thin plate portion 25a. In the temperature sensor 26, the thin disk portion 25a
The temperature of the fluid to be measured can be measured by contacting with the wall surface of the conduit through which the fluid to be measured flows, or by positioning the small diameter portion 5a of the covering member 5 in the fluid to be measured.
As described above, the shape and dimensions of the heat transfer member are not particularly limited as long as the heat quantity of the fluid to be measured can be effectively transmitted.

Further, in the above embodiment, the concave portion 10 is formed in the substrate 6, the air layer is provided by sealing with the preparation 11, and the insulating layer 7,
9, the temperature sensing unit 2
However, such a configuration is not necessarily required.

Further, in the above embodiment, the covering member 5 of the temperature sensor 1 is composed of a large diameter portion and a small diameter portion. However, the shape and size of the covering member 5 may be appropriately determined in consideration of the mounting state. Of course, it can be changed.

[0030]

As described above, according to the temperature sensor of the present invention, it is possible to perform high-precision temperature measurement in a local part, to reduce the manufacturing cost, and to improve the environmental resistance. Can be improved.

[Brief description of the drawings]

FIG. 1A is a front sectional view and FIG. 1B is a side sectional view showing an embodiment of a temperature sensor according to the present invention.

FIG. 2 is an exploded perspective view of a temperature detecting section of the temperature sensor according to the embodiment of the present invention.

FIG. 3 is a longitudinal sectional view of the same.

FIG. 4 is an explanatory view showing a manufacturing process of one embodiment of the temperature sensor of the present invention.

FIG. 5 is a perspective view of one embodiment of the temperature sensor of the present invention.

FIG. 6 is a longitudinal sectional view showing a method for measuring the temperature of a fluid flowing through a conduit using the temperature sensor of the present invention.

FIG. 7 is a perspective view of another embodiment of the temperature sensor of the present invention.

FIG. 8 is a longitudinal sectional view of a conventional temperature sensor used for a cooling and heating device.

FIG. 9 is a longitudinal sectional view of a conventional temperature sensor used for a water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Temperature sensor 2 Temperature detection part 3 Heat transfer member 4 Output terminal 5 Covering member 6 Substrate 8 Temperature sensing body 13 Bonding wire 25 Heat transfer member 25 25a Rectangular thin plate part 25b Thin disk part

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[Procedure amendment]

[Submission date] April 20, 1998

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Change

[Correction contents]

FIG. 3

FIG. 8

FIG. 9

FIG.

FIG. 2

FIG. 4

FIG. 5

FIG. 6

FIG. 7

Continued on the front page (72) Inventor Yoyo Kobayashi 1-17-17 Numakage, Urawa-shi, Saitama Mitsui Kinzoku Mining Co., Ltd. Thermistor Division

Claims (3)

[Claims] 1. A temperature detecting section formed by forming a temperature sensing element on a substrate is fixed to an end face of a heat transfer member, and the temperature detecting section and an output terminal are connected by a bonding wire. A temperature sensor, wherein a heat transfer member and a half of an output terminal are covered with a covering member molded. 2. The temperature sensor according to claim 1, wherein the heat transfer member is a rectangular thin plate. 3. The temperature sensor according to claim 2, wherein the heat transfer member is formed by fixing a thin disk portion to a tip of a rectangular thin plate portion.